Work holder

ABSTRACT

A work holder capable of holding a work piece having a generally arcuate circumferential body portion, to give location, baring, and rotating support to said body portion while presenting another body portion of said work piece for grinding and like operations. The invention device features simplified and improved holding means including unique roller modules which per se incorporate their drive means and have simple means adapting them to mount various size work pieces without loss of efficiency. It also provides a continuous drive system for such modules distinguished by precision control means affording a maximum use of applied power. It is further characterized by the application of O-rings to at least one roller module in a manner to exert a balanced and positive rotative influence to the workpiece. Means are provided to precisely reference a work piece to a cutting tool and to simply induce an angular disposition of or apply an axial driving force to a work piece during a cutting operation.

United States Patent Stevens et al.

[5 1 WORK HOLDER [72] Inventors: Harry G. Stevens, 1029 Ter racewoodDrive, Englewood, Ohio 45322; Robert Earl Smith, 4224 Scrubb Drive,Kettering, Ohio 45429 [22] Filed: April 29, 1970 211 Appl. No.: 32,928

[52] US. Cl ..214/340 [51] Int. Cl ..B65g 7/00 [58] Field of Search..214/333, 339, 340; 198/127 [56] References Cited UNITED STATES PATENTS3,278,060 10/ 1966 Cooper ..214/340 2,519,837 8/1950 Lampard ..214/3403,178,047 4/1965 Norton ..214/339 3,448,877 6/1969 Pandjiris et al...214/340 3,434,610 3/1969 Wilson ..214/339 Primary Examiner-Gerald M.Forlenza Assistant Examiner-Jerold M. Forsberg Att0rney-Jerome P. Bloom[4 1 Oct. 3, 1972 [57] ABSTRACT A work holder capable of holding a workpiece having a generally arcuate circumferential body portion, to givelocation, baring, and rotating support to said body portion whilepresenting another body portion of said work piece for grinding and likeoperations. The invention device features simplified and improvedholding means including unique roller modules which per se incorporatetheir drive means and have simple means. adapting them to mount varioussize work pieces without loss of efficiency. It also provides acontinuous drive system for such modules distin guished by precisioncontrol means affording a maximum use of applied power. It is furthercharacterized by the application of O-rings to at least one rollermodule in a manner to exert a balanced and positive rotative influenceto the workpiece. Means are provided to precisely reference a work pieceto a cutting tool and to simply induce an angular disposition of orapply an axial driving force to a. work piece during a cuttingoperation.

' 18 Claims, 10 Drawing Figures PAIENIEnum m2 3.695.468

SHEET 1 OF 4 INVENTORS HARRY G. STEVENS ROBERT EARL SMITH A TTORNE YPMENTED I973 3,695,468

sum 2 or 4 22 m/vzlvrons HARRY G STEVENS ROBERT EARL SMITH A TTOR/VE YPAIENTEDnm 3 nm e G BLOCK M/VE/VTORS HARRY- G. STEVENS ROBERT EARL SMiTHBY WPTBM ATTORNEY FlG- IO' WORK HOLDER BACKGROUND OF THE INVENTION:

This invention is directed to the simplification and improvement of workholders with a view to rendering them move versatile in use and moreefiicient and satisfactory for a wider variety of applications. It isparticularly advantageous in application to fabricating and maintainingpunches and like tools or products distinguished by a generally rod orcylinder form in the first instance and will be so described, though notso limited in application.

Many work holders have been designed heretofore for holding objects ofsmall character and variable length which must at the same time bedriven at high speed to be either worked on themselves or applied toproduce work on other objects. There are a multitude of such devicessubject of prior patents such as, for example, the Gargrave U. S. Pat.No. 3,145,861. Each patent of this nature has directed its attentionprimarily to means and methods of holding, rotating, and driving smalldiameter work pieces by roller means of various design and with a view,in most cases, to enable an inter-nesting relation of the roller meansto achieve the control of the work piece. The prior art devices have hadvarying degree of success but no one has shown as great a versatility asrequired or desired for the multitude of present day applications whichpresent themselves in a single fabricating installation. Moreover, theirability to achieve precision results and to operate with maximal use ofapplied power and a minimum of attention generally has not been provenin practice.

DESCRIPTION OF THE INVENTION It is a primary object of the presentinvention to over- I come the general deficiencies in prior artworkholders for the purposes described to achieve, in an economical fashion,one which is more efficient and satisfactory in use, adaptable to a widevariety of applications and susceptible of operation substantiallywithout occurrence of malfunction.

Another object of the invention is to provide an improved work holdercapable of use to insure precision results.

A further object of the invention is to provide a unique roller modulefor work holders.

An additional object of the invention is to provide an improvedarrangement for mounting a work piece of, at least in part, acylindricalbody form for rotation about its longitudinal axis for work to be doneon or by a projected portion thereof, said arrangement incorporatingmeans for a variable precision orientation of the projected portion ofthe workpiece.

Another object of the invention is to provide a work holder for the usedescribed possessing improved driving control means for rollerssupporting thereon a work piece.

A further object of the invention is to provide a rotating mount forwork pieces having simple means for varying their relative dispositionto selectively accomimodate the work piece as to its size, desiredattitude and character of movement for work thereon or thereby.

Another object of the invention is to provide improved holding means forcontaining a work piece to a mount inducing the rotation thereof forwork to be done thereon or thereby.

An additional object of the invention is to provide a work holderpossessing the advantageous structural features, the inherentmeritorious characteristics and means and mode of use herein described.

The embodiments of the invention here illustrated comprise a simple baseincluding to one end an offset arm mounting a drive motor geared todirectly drive, preferably through one continuous belt, unique rollermodules which mount a work piece. One roller module mounts eccentricallyof a rotatable shaft, a simple adjustment of which is sufiicient toaccommodate the application to said roller modules of work pieces ofvarious diameter. The roller modules commonly mount to a tiltablebracket capable of precision adjustment to orient the axis of a workpiece as desired. The same bracket mounts a lever embodying a thirdelement for containing a work piece to the rolller modules under avariable selected degree of compression. The roller modules incorporate,in at least one instance, resilient O-rings designed to produce a mostpositive drive and balanced control of the work piece in effecting itsrotation. Unique means are also provided to achieve, in a. simplefashion, a taper on a work piece and/or an axial movement of a rotatingwork piece as held to and driven by the inventive structure.

The above noted features as well as others provided by the invention andtheir structural detail will become self evident from the followingillustrations of preferred embodiments.

With the above and other incidental objects in view as will more fullyappear in the specification, the invention intended to be protected byLetters Patent consists of the featuresof construction, the parts andcombinations thereof, and the mode of operation as hereinafter describedor illustrated in the accompanying drawings, or their equivalents.

Referring to the drawings where some but obviously not necessarily theonly forms of embodiment of the invention are shown: v

FIG. 1 is a front elevation view of a work holder in accordance with theinvention;

FIG. 2 is a top view of the structure of FIG. 1;

FIG. 3 is a fragmentary view of the drive system, taken on line 3-3 ofFIG. 2;

FIG. 4 is a view taken on line 4-4 of FIG. 2;

FIG. 5 is a view taken on line S5 of FIG. 1;

FIG. 6 is a fragmentary view, partly in section, taken on line 66 ofFIG. 2 and illustrating the tilt controls for the work mounting bracketof the device of FIG. 1;

FIG. 7 is a fragmentary view, partly in section, illustrating theversatility of the work holder in application to the forming or guidingof a punch;

FIG. 8 is a detail of the skew holding roller embodied in the device ofFIG. 1; and

FIGS. 9 and 10 illustrate front and side views of a reversible work holddown device which may be applied to the clamping lever for a work piecein lieu of the skew roller illustrated in preceding Figures.

Like parts are indicated by similar characters of reference throughoutthe several views.

DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION:

A preferred embodiment of the invention shown in the drawings includes arectangularly formed base 10. Angled upwardly from one end and to therear edge of base is an integrally formed arm 11. The projectedextremity of the arm 11 presents an elevated horizontal platform 12 onwhich is mounted a drive motor 13. Formed in the platform 12 areparallel slots 14 which are oriented parallel to the front edge of thebase 10. The slots 14 receive therethrough bolts 15 the heads of whichdispose to the underside of the arm 11 and the upper extremities ofwhich are threadedly engaged in the base of the drive motor. The bolts15 function as conventional clamping devices by means of which the motor13 can be secured in any desired position which can be accommodatedwithin the limits of movement of the bolts 15 as predetermined by thelength of the slots 14. The purpose of this will be further described.

Utilizing conventional means, there is 4 a power takeoff at right anglesto the motor drive shaft through the medium of a power transmissionshaft 16. The shaft 16 is oriented to project forwardly on the base 10and has fixed in connection with its projected extremity a toothed gearbelt pulley l7. Looped about the pulley 17 is one end of a continuousgear belt 18. The belt 18 extends from the pulley 17 to move in a senseupwardly over a gear belt pulley 19, down around an idler wheel 20, thenup over a gear belt pulley 21, down around a centrally channelled beltguide idler wheel 22 and back to the pulley 17. It will be seen from thedrawings that the channelled idler 22 has a deep central groove in itsperiphery and is so positioned and formed that simultaneous with itsfunction as an idler it will nest and laterally contain the belt 18 asit passes under and about the idler 20 to move to the gear belt pulley21. It will be seen, therefore, that the idlers 20 and 22 have a matingfunctional relation. As will become evident from a further descriptionof the invention structure, the idlers act commonly to influence notonly a proper direction and alignment of the belt 18 at the idlers butthroughout the complete run of the continuous belt. The arrangement issuch that there will be no slippage of the belt on the driven elementsand the belt will be inhibited from lateral travel from the desiredplane of its operation. The net result achieved is an optimal drivingefficiency and minimal belt wear; As will be further seen, the positionand application of the idlers in the invention structure is such thatwith a relative adjustment of one or more of the gear pulleys thatsatisfactory belt tension can be easily maintained.

Looking now to the base 10, formed integral with its upper surface is agenerally rectangular block-like projection forming a pad 30. In theupper surface of pad and in a line parallel to the plane of thecontinuous belt 18 is a coextensive V-formed groove 31. The groove 31nests coextensively therewith a pivot rod 32 which has a uniformdiameter. The sizes of the groove 31 and the rod 32 are such that as therod 32 nests in the groove 31 a diameter thereof positions substantiallyco-planar with the upper surface of the pad 30. Superposed on each ofthe respective ends of the pad 30 is a generally rectangular guide bar33. The bars 33 serve to nest and confine the respective ends of thepivot rod 32, having complementary V grooves 34 in their bottoms toaccommodate the same. Extending between and laterally confined by theguide bars 33 is the base of a mounting bracket 35. The mounting bracket35 has in side elevation a generally right angled configuration, one arm36 thereof projecting generally vertically of the base 10,

relatively centered over the rod 32 to which it is secured at pointsspaced longitudinally of the rod by screws 25. As seen in the drawings,the bracket 35 at the base of its arm portion 36, in the area where itis secured to the pivot rod 32, has a shallow channel to partially nestthe upper projected surface of the rod.

It will be seen that this channel accommodation of the pivot rod 32 bythe undersurface of the bracket 35, in an area thereof adjacent theforwardmost limit of the bracket, establishes a vertical spacing betweenthe base of the bracket and the uppermost surface of the pad 30.

The other arm 37 of the bracket 35 provides what might be considered thebase of the bracket, extending generally horizontally andin a senserearwardly over the base 10. To the rear of the pad 30 and in a cornerthereof at an edge most adjacent the drive motor 13, the arm 37 hasformed therein an aperture 38. Threadedly engaged in and projectingvertically from a rear corner of the base 10 is a screw 39 which extendsupwardly, with substantial clearance, through the aperture 38. The lowerend of the screw 39 is fixed against rotation by an appropriatelyapplied set screw. immediately above and below the arm 37 of the bracket35 is a set of spherical seating washers, each set being confined inreference to the arm 37 by a nut 41 on the screw 39. As will be evidentfrom the drawings, the elements of each set of washers comprise a firstwasher 42 the base of which seats against the adjacent surface of thearm 37 with clearance in respect to the screw 39.

The outermost surface of the washer 42 has a recess formed as a segmentof a sphere. This recess accommodates a complementarily formed surfaceon the mating washer 43 of the set. The outermost surface of the washer43 is flat. It will be readily seen from FIGS. 4 and 7 of the drawingthat the bracket 35 may be tilted forwardly or rearwardly with referenceto the base 10, to the degree accommodated by the spacing between thebracket and the pad 30, and this tilting can be readily accomplished onloosening of the nuts 41 of screw 39 to permit the relative adjustmentof the complementary spherical surfaces of the sets of washers abuttingthe upper end lower surfaces of the arm 37 within the limits of the nuts41.

Accordingly, since the bracket 35 has a rotatable base afforded by thepivot rod 32 which is confined for rotation to the base 10, on backingoff one of the nuts 41 in accordance with the direction of tilt desiredfor the bracket 35, one can then turn-up the other nut and fix theattitude of the bracket, a firm positioning of the bracket being insuredby the use of the spherical seat washers 42 and 43. Of course, a Inormal and zero setting for the bracket would be where the arm 37 is ina horizontal position.

Note that in the rear corner of the base 10 which is laterally remotefrom the screw 39, there is screwed a flat headed bolt 44 which may befixed against rotation in a conventional manner by a locking set screwapplied in the side of the base. In accordance with the invention, thehead of the bolt affords a plane of reference immediately above theupper surface of the base 10. Immediately above the head of the bolt 44in a corner of the arm 37 of bracket 35 which is remote from the screw39, there is fixed in the undersurface of the arm an element providing aspherical projection 46. The projection 46 is arranged so that when thearm 37 is horizontal its lowermost point of projection is generallycentered in respect to the planar surface of the bolt head thereunder.

The invention contemplates that a precision gage block may be insertedbetween the head of the bolt 44 and the projection 46 with the nuts 41in a backed off condition.'By the use of this gage block of precisiondimension one can then establish a precise zero setting for the bracket35, at which point the nuts 41 may be turned on screw 39 to achieve afixed position of the bracket. As mentioned previously, on backing offone of the nuts 41, one may then apply a precision gage block betweenthe head of the bolt 44 and the projection 46 to achieve a precise andcalibrated tilt of the bracket, upon which one can then turn up or downthe nuts to fix the calibrated adjustment of the position of thebracket.

As will be seen in further description of the invention structure, whenthe adjustment of the bracket 35 is to orient it in a zero position, asupported work piece will have its longitudinal axis preciselyhorizontal so that one can grind the same, for example, in any portionthereof with no taper resulting. correspondingly, a tilting of thebracket from the zero reference position will position a work piece soas to enable and insure a precise taper in a conventional grindingprocedure.

it is noted that the invention structure is, designed so the dimensionfrom the contact point of spherical projection 46 to the pivot center ofthe bracket provides a moment arm which is compatible with publishedstandard tables such as those in Machinerys Handbook so that apredetermined gage block applied between the projection and the bolthead 44 will create a predetermined angle of adjustment for a supportedwork piece.

At the upper end of the vertical arm 36 of the bracket 35 are laterallyspaced co-planar projections 50 each having an identical throughaperture 51. The central axes of the apertures 51 are parallel and rundirectly from front to rear of the base 10. The aperture 51 in theprojection 50 most adjacent the motor 12 receives therein an enlargeddiameter portion of a shaft 52 having a tapped recess in the end thereofto the rear ture 51 terminates immediately forward of the projection 50in an external flange 55. Accordingly, when the enlarged portion of theshaft 52 is inserted in the forward face of the projection 50 to enterits accommodating aperture 51 and the retainer plate 53 and screw 54applied to the rear of the projection, on engaging and fixing the screwthe flange 55 will be drawn into an abutting relation with the adjacentprojection 50 and the shaft is thereby fixed to the arm 36. The shaft 52includes a reduced diameter portion 56 which projects forwardly of theflange 55 and perpendicular to the forward face of the adjacentprojection 50.

Slip fit on the reduced shaft portion 56 are a pair of precision matchedroller bearings 57 spaced by a complementary spacer 58, the assembly ofwhich is contained to the shaft flange 55 by application to theoutermost end of shaft portion 56 of a retainer plate 59 secured to theprojected end of the shaft portion 56 by a screw. The bearing assemblythus defined mounts coextensively therewith a roller module 60. Themodule 60 has a sleeve form and immediately adjacent the flange 55 whichit abuts it is substantially reduced in external diameter to accommodateand fixedly mount thereabout the gear pulley 19. The latter is containedto a shoulder formed by the reduction in external diameter of the innerend of the module by a bearing retainer plate, means being provided sothat the pulley is integrated with the roller module. Outwardly of theexternal toothed gear pulley 19 the relatively thicker body portion ofthe module sleeve 60, the interior diameter which is uniform, has formedon the exterior thereof longitudinally spaced, circumferential radialprojections 61 and 62. The projection 62 is coincident with the outerextremity of the module. The projections 61 and 62 define therelbetweenan annular channel 63. There is formed centrally and circumferentiallyof each of the projections 61 and 62 a shallow groove 66 which has amodified V form, the side walls of the V converging at inclinations ofabout 15 to terminate at a flat base which forms a truncated apex on theV. Each of the grooves 66 accommodate the circumferential seatingtherein of a resilient O-ring 67. In accordance with a preferred conceptof the invention the grooves 66 are of a size and depth which areproportioned to the sectional diameter of the applied 0- ring 67 so thatthe surface of the O-ring extends above the diameter of the rollermodule by a controlled amount, preferably approximately 0.010 inches. Itis noted that the shape of the groove 66 is significant in that themodified V form of its cross section provides space for the O-rings todeform radially instead of circumferentially. As a result, in use of theO-rings, as will be further described, there is a substantial reductionof the circumferential creep which would occur otherwise. Theconsequence of this is a decrease in wear of the O-rings and asubstantial lengthening of their effective operating life.

The vertical projection 50 of bracket 35 most remote from the drivemotor 12 has rotatably nested in the aperture 51 thereof a rear segmentof a shaft 70 including a radially projected external flange portion 71which abuts the forwardmost face of the bracket arm 36. Adjacent therear of the arm 36, the one end of the shaft 70 is provided withdiametrically opposite flatted sides 72. This. rear end of the shaft 70which projects from the bracket arm 36 nests in a complementary shapedrecess in a control cap 73. The control cap is secured to the shaft 70by a screw 64. The arrangement is such that the portion of the shaft 70between flange 71 and the control cap is rotatably mounted in thebracket arm 36, the rotation being possible through the medium of arotation of the cap 73 as will be further described. Forwardly of flange71 the shaft 70 has a reduced diameter portion 74 which projects ineccentrically offset relation to the axis of the portion of shaft 70which is rotatably mounted within the bracket arm 36. The reduceddiameter eccentric projection 74 has contained thereon an assembly ofmatched bearings 57' of a nature and contained in a manner as bearings57 on the shaft segment 56. Moreover, rotatably mounted on this bearingassembly is a roller module 60 identical with that previously described.It is noted that in some cases it may be preferred that the grooves 66be eliminated to present smooth circular exteriors on the projections 61and 62. Of course, in such case the O-rings 67 will be eliminated also.However, in this instance it is preferred, as illustrated, forsimplicity of manufacture, that the roller modules 60 and 60 beidentically formed. Of course, this enables interchangeability of parts,a desirable feature. In the case of the roller module 60, the gear beltpulley thereon will correspond here to the pulley 21. Since the pulleys60 and 60 are identical in substance, it would appear that no furtherdetail of the pulley 60 is necessary, except to note in the preferredembodiment it requires no O-rings.

Noting the drawings, directly below and to the left of center of thelast mentioned roller module there is anchored in and perpendicularlyprojected from the forward face of the bracket 35 a bolt-like devicewhich mounts immediately adjacent and in abutting relation to thebracket a spacer 76, a washer 77 and the idler 20 which rotatably mountsthereon. Of course, a suitable washer is provided adjacent the head ofthe bolt and to the outer face of the idler roller so it may turn freelyin respect to the pivot which is provided therefor by the bolt.

Immediately below and to the right of the pivot for idler 20 the bracket35 has in connection therewith a pivot for the idler 22. With particularreference to the showing in the drawings, it is again noted that in theperiphery of idler roller 22 is a deep circumferential channel of awidth to accommodate the movement of the gear belt 18 thereunder in anarea diametrically opposite the location at which another portion of thebelt passes under the idler roller 19. It will be seen that the idlerroller 22 is positioned to nest the portion of the belt passing underand up from the idler roller 19. In this manner, there is a dualvertically spaced control of the continuous gear belt 18 to insure itsprecision location and optimal control for best driving efficiency inrespect to the elements with which it is interengaged.

Attention is directed to the fact, once more, that by a mere rotation ofthe cap 73, the shaft 70 which is connected therewith may be rotated tovariably position its forwardly projected eccentrically disposedextension and thereby move the roller module which mounts thereon to andfrom the adjacent module which has a relatively fixed position of itsaxis as defined by the mounting shaft portion 56.

Projected upwardly and to the side of the bracket 35 remote from motor12 is an integrally connected arm 80. Pivoted to the projected extremityof the arm 80 and reversely directed to overlie the same is a lever 65.Formed in the arm 80 intermediate its ends is a vertical through slot 82which in opposite side wall portions most adjacent the end immediatelyforward of the pivot for the arm 65 has aligned apertures. The latteraccommodate for rotation therein the ends of the pivot pin 83 whichdisposes in transversely bridging relation to the slot 82 at a locationimmediately adjacent the module 60' to its side remote from the module60. The pivot 83 mounts in a sense essentially parallel to the shaftsmounting the roller modules and projects through and is engaged to thelower end of a large screw-like member 84. The member 84 projectsupwardly in a plane common to the arm 80 and through a slot 85 in theoverlying lever 65. Immediately over the lever the screw-like member 84mounts thereon a washer 86 spherically contoured on its underside whichbears on a pair of cam-like vertical wall sections 87 projected alongeither side of the slot in lever 65 in a sense at right angles to theshafts or axes of the roller modules. Contained in a sleeve 88 about thescrew member 84 above the washer 86 is a coiled spring 89. Spring 89-projects above the sleeve 88 to be contained by a sleeve-like cap 90 thebase of which is threadedly engaged by the screw member 84 whichprojects therethrough. It will be readily seen that as the cap 90 isthreaded down about the screw member 84, noting FIG. 1, the cap willtelescope about the short sleeve 88 above the washer 86. It is notedthat the sleeve 88 has calibrations so one may predetermine the forcesupplied by a selective adjustment of the cap sleeve 90.

Looking now to the vertical wall projections 87 orienting to either sideand the length of the slot 85, at their ends most adjacent the leverpivot the projections are sloped upwardly at an angle to the top surfaceof the lever of approximately 20 to 40. From a peak the tops of the wallprojections uniformly slope downwardly except for immediately followingthe peak on the down slope is a latching depression or dimple 91.

At its end remote from its pivot the lever 65 has a transverse throughpassage 92. At the end of the lever adjacent and forwardly of its pivot,there is mounted in the bracket arm immediately thereunder a springbiased plunger the influence of which is to apply a bias of lever 65 ina sense clockwise about its pivot.

Returning now to the through passage 92 at the projected extremity ofthe lever, when the lever is in a depressed position wherein it assumesa substantially horizontal orientation, the central axis of the throughpassage positions relatively central to the roller modules, in a sensefore and aft of the base 10. Slip fit in the passage 92 to projectforwardly therefrom is a pin-like shaft 93 which has in the body thereofdiametrically opposite flats 94. In mount of the pin 93, the bodyportion thereof including the flats 94 is inserted in the passage oraperture 92 to be held by a single set screw engaged through the lever65 to abut one or the other of the flats 94, depending on which ispositioned uppermost. The portion of the shaft 93 which is within thelever 65 has its axis generally parallel to the axes of the rollermodules. However, the extremity of the shaft 93 which projects forwardlyof and relatively above the roller modules has its exterior surfaceturned down about an axis angled at 45 minutes to 1 degree to thelongitudinal axis of the remainder of the shaft. This angled outer endportion 95 and the way the shaft is uniformly turned down to create thisangle produces an angularly inclined shoulder 96. The shoulder dictatesthe position of a roller 97 which is applied on the angled end portionof the pin shaft 93. By this means, depending on which flat ispositioned uppermost to hold the pin 93 in a particular orientation, theangle at which the portion 95 is disposed is directly changed to anopposite position. There is thus provided a telescoping two directionalskew roller which may be moved laterally parallel to the longitudinalaxis of a work piece held and ground, for example, and maintained at thesame angle of skew and still contact the work piece at a constant radiallocation. The significance of this will be further described.

Further included in connection with the bracket 35, to its rearhorizontal portion is mounted a bearing 98 through which is projected ahorizontally oriented rod 99 serving as a rearward stop for a workpiece. The stop 99 is axially adjustable and may be secured in anyselected position by means of a set screw engaged thereto through itsbearing support.

There is also provided immediately over the pad 30 in connection withthe bracket 35 and projecting perpendicular to its front face andforwardly thereof a shaft 100. In the center of the projected extremityof shaft 100 is threadedly engaged a screw 101. The screw 101 is acap-type screw and the body thereof projects through an elongate slot103 in a bar-like member 104 which is to serve as a front stop memberfor a work piece. As is' evidenced in FIG. 1 of the drawings, onsufficient release of the cap screw in reference to the bar 104, it maypivot about the body of the screwto a position displaced from a workpiece. When in use, the cap screw can be released and the bar 104positioned perpendicular to the base and serve as a front stop for awork piece such as indicated in FIG. 7.

Let us now consider the use of the invention structure above described.For example, if rod stock is to be placed in the work holder to beworked to a punch form, one end thereof may be laid in the nest definedbetween the uppermost adjacent surfaces of the roller modules 60 and60'. As laid in, the cap 73 on the shaft 70 may be turned toeccentrically move the shaft portion 74 to a position that the bodyportion of the work piece or stock of cylindrical form will be optimallynested between the roller modules. In the one case, to one side thereofthe so based body portion of the work piece will be in engagement withthe projected portions of the O-rings 67 to be resiliently based thereagainst. On the other side the roller module 60' will afford fourlongitudinally spaced annular bearing surfaces balancing the body of thestock. Disregarding the front and back work stops in this instance, onecan then move the arm in the form of the screw 84, its full lineposition shown in FIG. 1, to its dotted line position. Depending on thedimension of the work piece and the pressure to be applied thereto, thescrew sleeve or cap 90 is appropriately adjusted to afford a proper biasthrough the spring 89 to the spherically contoured washer 86 which bearson the cam surfaces of the projections 87 on the lever 65. It willbereadily seen that as the washer 86 is pushed upwardly on the slope ofthe cams 87, the projected extremity of the lever 65 is caused to bedepressed against the bias thereon. As the washer is carried by thescrew-like member 84 up over the peak of the cam, the skew roller 97 iscaused to bear on an uppermost surface of the body portion of the workpiece which is balanced on and between the roller modules 60 and 60f. Asthe washer 86 moves over the peak of the cams 87, there is a resilientaccommodation of any reactive force by the spring 89 and thereafter arelief as the spherical surface of the washer 86 seats in the dimples 91in the cam surfaces.

Where the axis of the round stock or rod stock is to be maintainedhorizontal for working a projected extremity thereof which extendsbeyond the roller modules, the work holder will be oriented asrepresented in FIG. 4 of the drawings. This is the zero position whichhas been appropriately established as illustrated in FIG. 6. Here it isshown that a gage block precision form to indicate a zero position isplaced over the flat head of the bolt 44 and with the nuts 41 released,the horizontal'arm 37 of the bracket 35 is positioned so the projection46 is in precise contact with the gage block. When this occurs, the nuts41 may positioned with its longitudinal axis absolutely horizontal andthe projected end thereof is presented for reduction to form the desiredpunch. Reference. is made to the previous comment that the grooves 66for the O-rings are of a size and depth proportional to the sectiondiameter of the related O-ring 67 so the surface of the O-ring extendsabove the diameter of the roller module 60 a controlled amountsufficient to aid in the function or driving the workpiece throughfriction contact therewith. The work piece laying in the V between theroller modules is secured and held tight against the metal surfacesthereof by the roller 97 which is a pressure roller. The latter exertssufficient force against the work piece under the controlled biasthereon through the medium of the lever 65 to cause this to lie tightagainst the metal surfaces of the roller modules, continuouslydisplacing the rubber of the two O-rings 67,as they are rotatably drivenunder the influence of the gear belt 18 through the medium of theirintegrated gear pulleys l9 and 21. The work piece is rotated in thedesired directionv by its contact with both surfaces of the compressedO-rings 67 and with the metal circumference of the projections 61 and 62in which the 0- rings 67 nest. Whether a skew roller 97 is utilized asthe pressure roller, a roller in a plane common to a transverse planecommon to the roller modules or a device providing a pressure pointcontact is employed as a pressure medium, the roller modules with thepressure medium will always form a stable platform for the round body ofthe work piece as it is being rotated.

Attention is directed to the fact that in this specific embodiment ofthe invention shown in FIGS. 1 through 8, due to the significancethereof, the simple arrangement for a skew roller has been illustrated.As noted previously, dependent on which flat 94 is uppermost, the roller97 will be angled in reference to the longitudinal axis of the workpiece in one or the other of two directions which are oppositelyinclined to the longitudinal axis of the work piece. Depending on thedirection of the inclination, there will result on energizing the motor13 and drive of the roller modules through the medium of the belt 18,simultaneously with rotation of the work piece, an induced movement ofthe work piece in the direction of its longitudinal axis eitherforwardly or rearwardly from an established position. In this way, itmay be seen that a grinding or other cutting tool may be applied. to onesection of the work piece and move a portion of its length as determinedby the travel permitted. The front and rear stops may be suitablyutilized in an obvious manner to determine the degree of travelpermitted for the work piece in the sense of its axial direction asmounted to the roller modules. If the work piece is to be moved from aposition determined by a back stop outwardly a predetermined degree,then the front stop in the form of the bar 104 will be appropriatelypositioned from the adjacent end of the work piece in the firstinstance. The rear stop may be utilized in a similar manner.

The design and use of the skew roller as described is unique since underthe influence of the bias which is applied thereto through the medium ofthe arm 65, the shaft mounting the roller may be moved laterallyparallel to the longitudinal axis of the work piece, yet the roller willmaintain the same angle or skew and still contact the body of the workpiece at a constant radial location.

Attention is now directed to the operation and function of the eccentricmount provided for the roller module 60. As will be readily apparent,during the operation of the work holder the location of the rollermodule may be simply adjusted to best suit the diameter of the workpiece. Note that the adjustability of the module 60 to and from themodule 60 is infinite. The roller module 60' may be placed in oneextreme at a location nearly touching the roller module 60 at itsoutermost peripheral surface portions which include the rings 67. Fromthis location, by a rotation of the cap 73 one can achieve an eccentricaction producing infinite steps of adjustment of the roller module 60'away from the roller module 60 in a manner believed obvious. The degreeof adjustment may be easily made to suit increasing diameters of thework piece. This eccentric control and adjustment provides a means ofprolonging the potential operating life of the work holder. For example,when very small work pieces are clamped securely between the rollermodules, a very large radial load may be generated on the driven rollersand their supporting bearings. As the small work piece closelyapproaches the common center line of the large roller modules, theradial load on these rollers increases exponentially, though thedownward clamping force remains constant. Recognizing this fact, thefeature of the eccentric adjustability of the roller module 60 providesmeans permitting a skilled operator to easily adjust the center distanceof the roller modules and minimize the possibility of generating extremeradial load values.

The eccentric adjustability of roller module 60' also is important forreworking or reconditioning the workin g surfaces of the rollers. Forexample, by an eccentric adjustment of the roller module 60', one maymove the outer periphery thereof into firm contact with the roller 60and the mounted O-rings 67. In-this position, the roller module 60' maybe driven on energizing the motor 13 to rotate on its own axis and whenbrought into contact with the grinding wheel, its circumference may bere-ground very acciirately. It is obvious, of course, that if anyinaccuracy is produced by wear, it will tend to appear on the rollermodule 60'.

The eccentric mount of the roller module 60' is also important in thatthe adjustability as provided thereby eliminates the need for usingrollers of a specific or constant diameter. When a new or re-workedroller is used, the eccentric adjustability allows a correctrelationship to be easily achieved between the roller modules,regardless of the diameter of the roller 60, within rather wide limits.As will be apparent, this feature increases greatly the potential usefullife of the roller module of the invention.

To continue with the notation as to the importance of the variousfeatures of the invention structure previously described, attention isnow directed to the clamping device embodied in conjunction with thelever 65, as represented with the associated control arm defined by thescrew member 84, the biased spherically contoured washer 86, the spring89, the screw cap and the calibrated sleeve 88. In the instance of theillustration, the rear pivot for the arm 65 is placed at one remote endof the bracket arm 36 which commonly mounts the roller modules and theirparallel shafts. Further, the arm 65 is pivoted on the side of theroller modules most adjacent the eccentrically adjustable module 60'.When, for example, a diameter of an applied work piece is increased overthat previously worked and the roller module 60' is eccentricallyadjusted to move further and further away from the roller module 60, thedesign is such that the third or clamping roller or clamping devicemounted on the arm 65 will continue to exert a force on the work piecethe direction of which tends to remain normal to the center line betweenthe axes of the two roller modules. The invention, in respect to theclamp arm, does simply provide, also, a means for quick mount thereto ofany selected device for applying the control pressure point on the topof the work piece biased to the roller modules. In this respect,attention is directed to the device shown in FIGS. 9 and 10 of thedrawings.

Referring to FIGS. 9 and 10, one can use as a shaft inserted in theopening in the projected end of the arm 65, rather than the shaft 93, ashaft 113 which can have disposing within the passage 92 a shaft portionhaving diametrically opposed flats by means of which the shaft may beheld in one of two reverse positions by a set screw such as in the casefirst described. The difference here is that the projected end of theshaft 113 in this case which extends perpendicular to and forwardly ofthe arm 65 does not have a working of its end. Rather the axis of theentire shaft and its diameter is uniform. The projected end of the shaft113 is fixed in a vertically centered relation to a vertically orientednarrow plate 114 the respective ends of which are tapered. As shown inFIG. 9, at the apex of the upper taper is a rectangular slot receivingthe base of a blade 115 presenting a narrow fiat edge running from frontto rear and in a line parallel to the axes of the roller modules.Centered between the fore and aft extremities of the projected tip ofthe blade 115 is a notch 116 which divides the blade edge into fore andaft longitudinally spaced rectangular bearing portions 117 and 118. Nowlooking to the lowermost extremity of the plate element 114, thedependent apex is rounded to circumscribe immediately within the same anaperture in which is fixed a pivot pin 119. It is noted that thedependent apex of the plate 114 is reduced in thickness in a manner toleave it centered between the front and rear faces of the plate 114. Thepivot pin 119 has projections 120 of reduced diameter terminating in therespective front and rear planes of the plate 114. Each of theprojections 120, as seen in FIG. 10, mount a roller bearing 121.

Thus, when the skew roller previously described is not needed, it may bereplaced with the device afforded by the plate 1 14. As will beself-evident, where the hold down medium afforded on the arm 65 is thedouble roller bearings 121, the same will exert pressure atlongitudinally spaced points on the work piece held down between theroller modules. If the work piece is of extremely small diameter, thenthe plate 114 may be reversed by release of the set screw on its shaftportion 113 to reverse the flats thereon and the set screw reapplied,whereupon thin longitudinally spaced edge portions of the blade 115 maybe used to exert pressure on a very small diameter work piece and thesame will be effectively held and balanced while work is done thereon.

The extreme simplicity and versatility of this optionally positionedhold down unit of FIGS. 9 and 10 should be readily obvious. In a verysimple and effective manner there is achieved a highly utilitarian tool.

Not only is the tool effective but very economical to fabricate.

Attention is now directed to FIG. 7 of the drawings to illustrate yetother features of the invention. The deep central channel orcircumferential groove 63 in the roller modules can in the use of theinvention work holder serve specific and useful functions. These groovescan,in mounting work pieces such as short punches or short insert dieshaving expanded heads, serve to accommodate the expanded head in thesideby-side grooves 63 of the roller modules such as shown in FIG. 7.FIG. 7 shows also the orientation of the parts of the bracket controlswhere a tilting of the work piece is desired. Particular attentionshould be had in respect to the spherical seating washers adjusting toaccommodate the tilt of the bracket 35. There is also shown the usefulfunction of the utilitarian front and back stops that are so simplyincorporated in the invention structure.

It must be emphasized that the degree of flexibility and utility of thevarious components of the invention work holder makes them work inunison to achieve a degree of efficiency and accuracy not heretoforefound in prior art work holders. Moreover, one finds that even the veryelements of the work holder per se have general utility and they servewith considerable benefit in other equipment and for other purposes. Forexample the unique roller module concept of the invention provides aroller device which may be stocked as a unit and incorporates a drivemedium which can be used or not used, as needs require. The rollermodule can, of course, be made and stocked with an eccentric orconcentric shaft portion for mount thereof as needs require. Theconstruction which enables the embodiment therein of O-rings to achievea most effective engagement and drive is yet another advantage of theroller module per se.

Further, the drive system as afforded by the present invention isunique. Here we have a continuous arrangement of a gear belt whichprovides a simultaneous and conjoint drive of the rotating elements,which drive is uniformly effective, irrespective of the spacing betweenthe roller modules in the system as provided. A key feature is theunique placement and relationship of the two idler pulleys, one of whichis small and smooth and the other which is channelled and functionsdually to control the belt moving over the smooth roller. By virtue ofthe arrangement, the drive belt is so maintained that there may besubstantially uniform tension throughout.

Above all the preceding, the sum and substance of the invention is thatthe components of the embodiments may be made inexpensively yet serve toachieve a most precise frame of reference for a round work piece so thatany work done thereon is true and precise in character. In use of theunique roller modules, the rubber O-rings function to smooth out andcompensate also for inaccuracies which might otherwise be produced inworking by the existence of grinding dust between the rollers and therollers and the work piece. If desired one may apply O-rings in thegroove 66 of the eccentrically mounted roller modules 60. But this isnot as desirable where smaller diameter work pieces are to be held androtated.

The foregoing is but an illustrative description of an inventionembodiment and some of the merits thereof. Other advantages andvariations in construction will be readily apparent to those versed inthe art and such is comprehended within the scope of the presentinvention.

From the above description it will be apparent that there is thusprovided a device of the character described possessing the particularfeatures of advantage before enumerated as desirable, but whichobviously is susceptible of modification in its form, proportions,detail construction and arrangement of parts without departing from theprinciple involved or sacrificing any of its advantages.

While in order to comply with the statute the invention has beendescribed in language more or less specific as to structural features,it is to be understood that the invention is not limited to the specificfeatures shown, but that the means and construction herein disclosedcomprise but one of several modes or putting the invention into effectand the invention is therefore claimed in any of its forms ormodifications within the legitimate and valid scope of the appendedclaims.

Having thus described our invention, we claim:

a pair of adjacent rollers mounting to said bracket, said rollers havingtheir axes disposed in parallel spaced .relation and being mounted toreceive a tubular or cylindrically formed work piece or operatingelement in bearing relation to upper adjacent surface portions thereof,means for effecting a selective containment of said work piece to saidrollers and one of said rollers having in connection therewith means forresiliently accommodating the mount of a work piece which means isoperable to function as a frictional drive means for said work piece asmounted to said rollers, said rollers being comprised in respectiveroller means, one of said roller means having in connection therewith ashaft which is in fixed relation to said bracket, the other of saidroller means having in connected relation thereto an eccentricallydisposed shaft mounting in bearing relation to said bracket and therebeing means for rotating said eccentrically disposed shaft to establishinfinitely variable degrees of spacing between the adjacent uppersurface portions of said roller means to accommodate work pieces oroperating elements of varying circumferential extent.

2. Apparatus as set forth in claim 1 characterized by a lever pivotallymounted on said bracket having, at a portion thereof displaced from itspivot, means for holding a work piece or operating element to saidroller means, means to normally bias said lever from a holding positionand means selectively disposable to clamp the holding means and thelever which mounts the same in a selectively biased relation to the workpiece.

3. Apparatus as set forth in claim 2 characterized by cam means on saidlever means and said clamp means being pivotally mounted to said bracketand operative on said cam means to control the position of said lever.

4. Apparatus as set forth in claim 3 characterized by said cam meanshaving a portion thereof defining a locking recess for said clamp means,the disposition of said clamp means therein establishing a firmlycontained position of the work piece or operating element to said rollermeans.

5. Apparatus as set forth in claim 4 characterized by said cam meanshaving upward and downward sloping surfaces as referenced to said lever,said clamp means including a cam follower means having an arcuatelycontoured surface following said cam means and said locking recess beingarcuately contoured to provide for the seating therein of said followermeans to provide a locked position of said lever and said holding means.

6. Apparatus as set forth in claim 5 characterized by said clamp meansincluding a screw device mounting a cap-like nut, and spring meansinterposed between said follower means and said cap-like nut to providefor a selective bias of said follower means to said lever.

7. A work holder including means defining abase, a bracket pivotallymounted on said base, means defining a pair of adjacent rollers mountingto said bracket, said rollers having their axes disposed in parallelspaced relation and being mounted to receive a tubular or cylindricallyformed work piece or operating element in bearing relation to upperadjacent surface portions thereof, means for effecting a selectivecontainment of said work piece to said rollers and one of said rollershaving in connection therewith means for resiliently accommodating themount of a work piece which means is operable to function as africtional drive means for said work piece as mounted to said rollers,said base including thereon pivot rod means and means containing saidpivot rod means for rotation on to said base, said pivot rod means beingconnected to form the base of said bracket to provide for tilting ofsaid bracket as and when needs require to establish a predeterminedorientation of the work piece or operating element.

8. Apparatus as set forth in claim 7 characterized by said brackethaving a right angle configuration including a generally horizontallydisposing arm and a generally vertically projecting arm, the saidvertically projecting arm mounting thereon said rollers and there beingmeans on said base and said horizontally projected arm to provide for acontrolled tilt of said bracket and the axes of said.

9. Apparatus as in claim 7 characterized by further means connectingsaid bracket to said base including a shaft-like device projectingthrough a portion of said bracket with clearance therebetween, means onsaid shaft-like device accommodating adjustment ..of said bracket in atilting motion on said base and for locking said bracket in a selectedattitude referenced to said base.

10. Apparatus as in claim 9 characterized by said shaft-like devicebeing threaded, at least in part, the threaded part passing through saidbracket and means having mating arcuately contoured surface portionsdisposing on said threaded part adjacent said bracket for accommodatingsaid bracket tilting motions.

l l. A work holder including means defining a base, a bracket pivotallymounted on said base, means defining a pair of adjacent rollers mountingto said bracket, said rollers having their axes disposed in parallelspaced relation and being mounted to receive a tubular or cylindricallyformed work piece or operating element in bearing relation to upperadjacent surface portions thereof, means for effecting a selectivecontainment of said work piece to said rollers and one of said rollershaving in connection therewith means for resiliently accommodating themount of a work piece which means is operable to function as africtional drive means for said work piece as mounted to said rollers,said means for selective containment of a work piece or operatingelement being hold down means constructed to have reverse positions ofapplication, said hold down means including roller means having a shaftmeans mounting the same to said bracket, said roller means being mountedat an angle to the axis of said shaft means, and said shaft means havingmeans defining selective p0sitions of application thereof to saidbracket to change the attitude of the connected roller means in itsapplication as hold down means.

12. A work holder including means defining a base, a bracket pivotallymounted on said base, means defining a pair of adjacent rollers mountingto said bracket, said rollers having their axes disposed in parallelspaced relation and being mounted to receive a tubular or cylindricallyformed work piece or operating element in bearing relation to upperadjacent surface portions thereof, means for effecting a selectivecontainment of said work piece to said rollers and one of said rollershaving in connection therewith means for resiliently accommodating themount of a work piece which means is operable to function as africtional drive means for said work piece as mounted to said rollers,said rollers including on the periphery thereof spaced circumferentialprojections adjacent of which define therebetween a channel, each ofsaid circumferential projections on at least one roller furtherincluding a circumferential recess.

13. Apparatus as in claim 12 including in each circumferential recess aresilient material a limited portion of which projects from the surfaceof the roller.

14. A work holder including means defining a base, a bracket pivotallymounted on said base including a vertically projected portion and ahorizontally projected portion, said vertically projected portionmounting thereon a pair of adjacent rollers the axes of which aredisposed in adjacent parallel spaced relation, said rollers mounting toreceive a tubular or cylindrically formed work piece or operatingelement in bearing relation to upper adjacent surface portions, saidbracket mounting thereon a lever including hold down means and means foroperating said lever to produce a triangular position of said hold downmeans as referenced to said rollers whereby to effect a controlledcontainment of the work piece to said rollers, said base having inconnected relation thereto a shaft-like member having threaded portions,said horizontal portion of said bracket having an aperture toaccommodate said shaft-like member to project therethrough withsubstantial clearance therebetween, nut elements on said threadedportions to opposite sides of said horizontal portion of the bracket andmeans interposed between said horizontal portion of said bracket, toeither side thereof, and said nuts to accommodate relative tiltingmovement of said horizontal portion of said bracket and provide a basefor a firm clamping thereof to said horizontal bracket portion by saidnuts.

15. Apparatus as set forth in claim 14 characterized by there beingadditional related means on said base and said horizontal portion ofsaid bracket to dictate a precision position of said bracket and saidroller means in reference to said base.

16. Apparatus as set forth in claim 15 characterized by said bracketincluding a projected arm portion mounting pivot means for said levermounting said hold down means, said bracket further mounting thereon apivot and in connection therewith a vertically projected clamping meansfor said lever,and said lever and said clamping means havinginterrelating parts in continuous bearing engagement, the adjustment ofsaid clamping means positioning said interengaging parts to achieve apredetermined bias of said hold down means to the work piece oroperating element bearing on said rollers.

17. A work holder, including support means, means defining a pair ofadjacent rollers mounting to said support means, said rollers havingtheir axes disposed in parallel spaced relation and being mounted toreceive a tubular or cylindrically formed work piece or operatingelement in bearing relation to upper adjacent surface portions thereof,individual shafts mounting said rollers eccentrically adjustable toeffect relatively eccentric adjustment of said rollers, and means foreffecting a selective containment of a work piece or operating elementin bearing relation to surface portions of said rollers, said last namedmeans including an anti-friction part adapted for individual skewadjustment.

18. A work holder, including support means, means defining a pair ofadjacent roller modules mounting to said support means, said rollermodules having their axes disposed in parallel spaced relation and beingmounted to receive a tubular or cylindrically formed work piece oroperating element in bearing relation to adjacent surface portionsthereof, the surface portions of said modules being identically formedwith one thereof providing longitudinally spaced apart circumferentiallands making a direct relatively unyielding contact with the work pieceand the surface portion of the other module having resilient ring meansrecessed in groove means between said circumferential lands forrelatively yielding frictional contact with the work piece, said groovemeans being of a size and depth proportional to the cross sectionalconfiguration of the resilient means so that said resilient means tendsnormally to extend above the surface portion of said other roller by acontrolled amount, said groove means being constructed to provide forradial displacement of said resilient means therein in response torotation of said roller modules in the presence of an applied selectivecontainment f the work piece to said modules and means for ef ectmg aselective containment of said work piece to the surface portions of saidroller modules.

I UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,695,468 Dated October 3, 1972 lri ent fl Harrv G. Stevens: Robert EarlSmith It is certified that error appears in the above-identified patent1 and that said Letters Patent are hereby corrected as shown below:

In the "ABSTRACT" line 3-, "baring" is corrected to read bearing Column10 line 3, of should be inserted after "block".

Column 15, Claim 8 last line, add rollers bfore the period.

Signed and sealed this 8th day of May 1973.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissionerof Patents C N- PO-ZGSO (10-69) USCOMM'DC 50376-P69 U.S. GOVERNMENTPRINTING OFFICE I969 0*366-J8l 3

1. A work holder including means defining a base, a bracket pivotallymounted on said base, means defining a pair of adjacent rollers mountingto said bracket, said rollers having their axes disposed in parallelspaced relation and being mounted to receive a tubular or cylindricallyformed work piece or operating element in bearing relation to upperadjacent surface portions thereof, means for effecting a selectivecontainment of said work piece to said rollers and one of said rollershaving in connection therewith means for resiliently accommodating themount of a work piece which means is operable to function as africtional drive means for said work piece as mounted to said rollers,said rollers being comprised in respective roller means, one of saidroller means having in connection therewith a shaft which is in fixedrelation to said bracket, the other of said roller means having inconnected relation thereto an eccentrically disposed shaft mounting inbearing relation to said bracket and there being means for rotating saideccentrically disposed shaft to establish infinitely variable degrees ofspacing between the adjacent upper surface portions of said roller meansto accommodate work pieces or operating elements of varyingcircumferential extent.
 2. Apparatus as set forth in claim 1characterized by a lever pivotally mounted on said bracket having, at aportion thereof displaced from its pivot, means for holding a work pieceor operating element to said roller means, means to normally bias saidlever from a holding position and means selectively disposable to clampthe holding means and the lever which mounts the same in a selectivelybiased relation to the work piece.
 3. Apparatus as set forth in claim 2characterized by cam means on said lever means and said clamp meansbeing pivotally mounted to said bracket and operative on said cam meansto control the position of said lever.
 4. Apparatus as set forth inclaim 3 characterized by said cam means having a portion thereofdefining a locking recess for said clamp means, the disposition of saidclamp means therein establishing a firmly contained position of the workpiece or operating element to said roller means.
 5. Apparatus as setforth in claim 4 characterized by said cam means having upward anddownward sloping surfaces as referenced to said lever, said clamp meansincluding a cam follower means having an arcuately contoured surfacefollowing said cam means and said locking recess being arcuatelycontoured to provide for the seating therein of said follower means toprovide a locked position of said lever and said holding means. 6.Apparatus as set forth in claim 5 characterized by said clamp meansincluding a screw device mounting a cap-like nut, and spring meansinterposed between said follower means and said cap-like nut to providefor a selective bias of said follower means to said lever.
 7. A workholder including means defining a base, a bracket pivotally mounted onsaid base, means defining a pair of adjacent rollers mounting to saidbracket, said rollers having their axes disposed in parallel spacedrelation and being mounted to receive a tubular or cylindrically formedwork piece or operating element in bearing relation to upper adjacentsurface portions thereof, means for effecting a selective containment ofsaid work piece to said rollers and one of said rollers having inconnection therewith means for resiliently accommodating the mount of awork piece which means is operable to function as a frictional drivemeans for said work piece as mounted to said rollers, said baseincluding thereon pivot rod means and means containinG said pivot rodmeans for rotation on to said base, said pivot rod means being connectedto form the base of said bracket to provide for tilting of said bracketas and when needs require to establish a predetermined orientation ofthe work piece or operating element.
 8. Apparatus as set forth in claim7 characterized by said bracket having a right angle configurationincluding a generally horizontally disposing arm and a generallyvertically projecting arm, the said vertically projecting arm mountingthereon said rollers and there being means on said base and saidhorizontally projected arm to provide for a controlled tilt of saidbracket and the axes of said.
 9. Apparatus as in claim 7 characterizedby further means connecting said bracket to said base including ashaft-like device projecting through a portion of said bracket withclearance therebetween, means on said shaft-like device accommodatingadjustment of said bracket in a tilting motion on said base and forlocking said bracket in a selected attitude referenced to said base. 10.Apparatus as in claim 9 characterized by said shaft-like device beingthreaded, at least in part, the threaded part passing through saidbracket and means having mating arcuately contoured surface portionsdisposing on said threaded part adjacent said bracket for accommodatingsaid bracket tilting motions.
 11. A work holder including means defininga base, a bracket pivotally mounted on said base, means defining a pairof adjacent rollers mounting to said bracket, said rollers having theiraxes disposed in parallel spaced relation and being mounted to receive atubular or cylindrically formed work piece or operating element inbearing relation to upper adjacent surface portions thereof, means foreffecting a selective containment of said work piece to said rollers andone of said rollers having in connection therewith means for resilientlyaccommodating the mount of a work piece which means is operable tofunction as a frictional drive means for said work piece as mounted tosaid rollers, said means for selective containment of a work piece oroperating element being hold down means constructed to have reversepositions of application, said hold down means including roller meanshaving a shaft means mounting the same to said bracket, said rollermeans being mounted at an angle to the axis of said shaft means, andsaid shaft means having means defining selective positions ofapplication thereof to said bracket to change the attitude of theconnected roller means in its application as hold down means.
 12. A workholder including means defining a base, a bracket pivotally mounted onsaid base, means defining a pair of adjacent rollers mounting to saidbracket, said rollers having their axes disposed in parallel spacedrelation and being mounted to receive a tubular or cylindrically formedwork piece or operating element in bearing relation to upper adjacentsurface portions thereof, means for effecting a selective containment ofsaid work piece to said rollers and one of said rollers having inconnection therewith means for resiliently accommodating the mount of awork piece which means is operable to function as a frictional drivemeans for said work piece as mounted to said rollers, said rollersincluding on the periphery thereof spaced circumferential projectionsadjacent of which define therebetween a channel, each of saidcircumferential projections on at least one roller further including acircumferential recess.
 13. Apparatus as in claim 12 including in eachcircumferential recess a resilient material a limited portion of whichprojects from the surface of the roller.
 14. A work holder includingmeans defining a base, a bracket pivotally mounted on said baseincluding a vertically projected portion and a horizontally projectedportion, said vertically projected portion mounting thereon a pair ofadjacent rollers the axes of which are disposed in adjacent parallelspaced relation, said rollers mounting to reCeive a tubular orcylindrically formed work piece or operating element in bearing relationto upper adjacent surface portions, said bracket mounting thereon alever including hold down means and means for operating said lever toproduce a triangular position of said hold down means as referenced tosaid rollers whereby to effect a controlled containment of the workpiece to said rollers, said base having in connected relation thereto ashaft-like member having threaded portions, said horizontal portion ofsaid bracket having an aperture to accommodate said shaft-like member toproject therethrough with substantial clearance therebetween, nutelements on said threaded portions to opposite sides of said horizontalportion of the bracket and means interposed between said horizontalportion of said bracket, to either side thereof, and said nuts toaccommodate relative tilting movement of said horizontal portion of saidbracket and provide a base for a firm clamping thereof to saidhorizontal bracket portion by said nuts.
 15. Apparatus as set forth inclaim 14 characterized by there being additional related means on saidbase and said horizontal portion of said bracket to dictate a precisionposition of said bracket and said roller means in reference to saidbase.
 16. Apparatus as set forth in claim 15 characterized by saidbracket including a projected arm portion mounting pivot means for saidlever mounting said hold down means, said bracket further mountingthereon a pivot and in connection therewith a vertically projectedclamping means for said lever,and said lever and said clamping meanshaving interrelating parts in continuous bearing engagement, theadjustment of said clamping means positioning said interengaging partsto achieve a predetermined bias of said hold down means to the workpiece or operating element bearing on said rollers.
 17. A work holder,including support means, means defining a pair of adjacent rollersmounting to said support means, said rollers having their axes disposedin parallel spaced relation and being mounted to receive a tubular orcylindrically formed work piece or operating element in bearing relationto upper adjacent surface portions thereof, individual shafts mountingsaid rollers in said support means, at least one of said shafts beingeccentrically adjustable to effect relatively eccentric adjustment ofsaid rollers, and means for effecting a selective containment of a workpiece or operating element in bearing relation to surface portions ofsaid rollers, said last named means including an anti-friction partadapted for individual skew adjustment.
 18. A work holder, includingsupport means, means defining a pair of adjacent roller modules mountingto said support means, said roller modules having their axes disposed inparallel spaced relation and being mounted to receive a tubular orcylindrically formed work piece or operating element in bearing relationto adjacent surface portions thereof, the surface portions of saidmodules being identically formed with one thereof providinglongitudinally spaced apart circumferential lands making a directrelatively unyielding contact with the work piece and the surfaceportion of the other module having resilient ring means recessed ingroove means between said circumferential lands for relatively yieldingfrictional contact with the work piece, said groove means being of asize and depth proportional to the cross sectional configuration of theresilient means so that said resilient means tends normally to extendabove the surface portion of said other roller by a controlled amount,said groove means being constructed to provide for radial displacementof said resilient means therein in response to rotation of said rollermodules in the presence of an applied selective containment of the workpiece to said modules, and means for effecting a selective containmentof said work piece to the surface portions of said roller modules.